UP to 800 trout are thought to have been killed at a fish farm in Abinger Hammer following a sewage leak this week.

The Environment Agency is investigating after receiving a call from a member of the public reporting that a substance believed to be sewage was entering the River Tillingbourne.

An officer arrived at Tillingbourne Trout Farm, off the A25 Guildford Road going out towards Gomshall, to find hundreds of fish dead or dying.

James Liney, an environment manager team leader at the agency, said: “This is a serious incident which is obviously devastating for the owner of the farm, where we estimate 700 to 800 trout have been killed.

“Environment officers were on site on Tuesday collecting evidence and sampling, and we have staff taking further samples from the river and doing some ecological monitoring.

“We don’t believe that the pollution incident has had any serious effect on the River Tillingbourne but has sadly had a major impact on the trout farm.”

The farm, which is also a licensed game dealer and has a fishery and shop selling fish which are smoked on site, allows visitors to buy fresh trout from the water or catch their own.

The Environment Agency believes it has traced the source of the pollution but said on Thursday that it was continuing to investigate.

Staff from the agency have in the past worked with fishermen to improve the habitat for fish in the River Tillingbourne, which also runs through Gomshall and Shere on its way to joining the River Wey at Guildford.

It is home to a healthy population of wild brown trout and coarse fish and also supports watercress farming.